Research will be conducted in order to determine how cadmium increases dental caries and how cadmium opposes caries prevention by fluoride. Studies will continue to determine how cadmium is metabolized by developing teeth. We will specifically determine if cadmium is associated with the organic or inorganic fraction of developing teeth. Studies will also continue to determine if cadmium alters the physical or chemical properties of developing teeth. Proposed measurements include Ca and P gradients with the electron probe, blood calcium levels, Knoop microhardness measurements, density gradient measurements of enamel and dentin, and bone radiographs. The experimental animal used will be the rat.